Engines use oil or other lubricants to enhance conductive heat transfer and to prevent overheating by limiting friction. Viscous fluids also serve as a limited leakage containment system and help reduce noise and vibrations within the engine when in operation. As fluids are used in the engine, they are degraded by coming into contact with small particles of metal or dirt from external sources. As oil degrades, it must be regenerated through replacement, introduction of new oil, filtration, or a combination thereof.
One of the most common method of filtration is the use of filtering cartridges secured to the engine where oil circulates. Traditional filters include a filtration media designed to trap particles of dirt and other residue as the oil migrates through the filtration media. Filtration through filtration media requires a driving force, often a pressure differential between the oil inlet and the oil outlet in the filter. As the filtration media traps dirt, the pressure required to push the oil through the filter increases. Because static filters are incapable of evacuating the dirt and residue, the filter increases in weight and reduces the overall efficiency of the engine. All static filters clog and thus require a release valve to bypass the filtration media. When these bypasses are opened, the filtration activity drops to zero.
Filter replacement requires the purchase, temporary storage, and installation of new filters. Discard of these filters also produces waste in the form of the casing in which the filtration media is stored. In addition to the cost associated with the purchase and maintenance of these filters, the loss of engine efficiency results in a higher fuel and oil cost for internal combustion engines.
What is needed is a self-cleaning filter of compact geometry that is capable of replacing cartridge filters known in the industry and improving engine efficiency.